Spark-plug.



W. S. THOMAS.

SPARK PLUG. APPLIICATION FILED FEB. 3, I916.

Patented Apr. 10, 1917.

wi lmeoo WM 6.

WILLIAM S. THOMAS, OF LOCK HAVEN, PENNSYLVANIA, ASSIGNOR OF ONE-HALF TOJAMES E. BUZZARD, OF LOCK HAVEN, PENNSYLVANIA.

' SPARK-PLUG.

I Specification of Letters Patent.

Patented Apr. 10, 19M.

Application filed February 3, 1916. Serial No. 76,027.

To all whom it may concern:

Be it known that I, WILLIAM S. THOMAS, a citizen of the United States,residing at Lock Haven, in the county of Clinton and State ofPennsylvania, have invented certain new and useful Improvements inSpark- Plugs, of which the following is a specification.

' My invention relates to improvements in spark plugs, and moreparticularly to spark plugs designed for use with internal combustionengines, an object of the invention being to so construct the severalparts of the plug that the gap between the electrodes can be adjustedwithout removing the plug, and provide an improved indicator which islocated on the upper portion of the plug, and which indicates the gapbetween the electrodes so that the operator can adjust which permits apriming fluid to be poured each plug to suit the working conditions ofeach cylinder.

A further object is to provide a spark plug of the character statedwhich permits a relatively wide or fat spark and which is composed of aplurality of parts easily assembled and easily kept clean.

A further object is to provide a spark plug into the cylinder throughthe plug, and which under normal conditions is tightly sealed.

A further object is to provide a spark plug of the character describedwhich can be operated to vary the length of gap, and permit theaccumulated carbon to be burned whenever desired by simply increasing'the length of the gap and the voltage of the electric current. v

With these and other objects in view, the invention consists in certainnovel features of construction and combinations and arrangements ofparts as will be more fully hereinafter described and pointed out in theclaims. I

In the accompanying drawings:

Figure 1 is a view in side elevation illustrating in full lines thenormal positions of the several parts, and in dotted lines otherpositions of adjustment.

Fig. 2 is a view in longitudinal section.

Fig. 3 is a top plan view, and.

Fig. 4 is a bottom plan view.

1 represents the body of the plug having a cylindrical bore 2, which atits lower end communicates with a circular recess 3 of larger diameterthan the bore 2, and a beveled seat 45- connects the recess 3 with thebore 2 for a purpose which will more fully hereinafter appear.

The body 1 has a screw-threaded end 5 to screw into the engine cylinder(not shown), and a stationary electrode 6 is fixed to the end of body 1,and cooperates with the movable electrode 7 in the ordinary way.

"This movable electrode 7 is in the form of a rod having a hook shapedlower end 8, which latter and the stationary electrode 6, are recessedas shown at 9, whereby anextended surface is offered to the electriccurrent as it leaps the gap, and insures a fatter spark than is possiblewith other forms of electrode. I y

The electrode 7 extends through a ring 10 located in the recess 3, andhas a shoulder 4 11 bearing against the ring, and normally holding thering against the seat 4 to insure a tight closure of the passage throughthe plug.

' A tube 12, of insulation, preferably fiber, is located in the bore 2,and is spaced from the ring 10 by a series of perforated disks 13,preferably of mica. In other words, the laminated mica disks 13 arepositioned be tween the end of tube 12 and ring 10, and the electrode 7extends through the ring 10, disks 13, and tube 12, and on its upperscrew-threaded end 14:, a nut 15 is positioned and operates to bind theshoulder 11 against the ring 10, and securely clamp the electrode inplace.

The upper end 14: of the electrode constitutes a binding post, and a nut16 is positioned thereon to clamp the conductor (not shown) thereto.

The tube 12, at its upper portion, is externally screw-threadcd as shownat 20, and two nuts 17 and 18 are located on this threaded portion 20,one nut operating as a jam for the other.

-To the lower nut 18, a bifurcated cam lever 19 is pivotally connected,and bears against the end of the body 1, so that this lever operates tomove the tube 12 longitudinally in the body,1, and normally holds thetube in one extreme position with the trodes 6 and 7. To indicate thislength of gap, a pointer 21 is fixed to a collar 22 which is securedby'a screw 23 around tube .12," and registers with a short scale 24 onthe end of body 1, hence indicating exactly the position of the movableelectrode.

It will be noted particularly by'referenee to Fig. 2, that an annulartapering recess 25 is provided between ring and the wall of recess3,.and this recess operates as a suction chamber from which any accumulaed oil or liquid is sucked outby the movement of theengine piston, hencepreventing any accumulation at their point to short circuit the sparkplug. 5

The ring 10 is provided with an annular depending flange 26 which actsas a wall, and prevents the formation of carbon to bridge thegap-between the electrodes. In other Words, carbon which forms aroundthe electrodes, adjacent the body of the plug,

cannot short circuit until accumulated in sufficient quantity to inclosethe flanged end of the ring, and this carbon can be readily burned fromtime to time by simply length ening the gap between the electrodes andincreasing the voltage of the current without removing the spark plug.

. The priming may be permitted from time to time by swinging the lever19 on its pivot to the dotted line position shown in Fig. 1, and thenpouring the gasolene or other hydro-carbon oil through the bore 2, as itwill be noted that the bore 2 is of greater diameter than tube 12, andsufiicient space is provided for the passage of the liquid.

The ring 10, however, normally seals the plug, but when moved away fromthe seat 4 by the action of the lever 19, permits the entrance of theliquid into the cylinder.

The parts are so arranged that their move ment from time to timedislodges carbon which might otherwise accumulate to short circuit theplug, and it will be noted that the several parts are capable ofadjustment tovary the spark and to permit a ready assemblage of thecomponent elements of the lug. I

p Various slight changes might. be made in the general form andarrangement of parts described without departing from my invention, .andhence I do not limit myself to the precise details set forth, butconsider myselfat liberty to make such changes and alterations as fairlyfall within the spirit I and scope of the appended claims. Having thusdescribed my invention,.what T claim as new and desire to secure byLetters atentis:

1. The combination in a spark plug, of a body portion having a boreextending therethrough, a tube extending into and having a diametersmaller than the bore thus proand extending to the outer surface of thebody portion, said body portion having a recess at its innermost end,said recess being of larger diameter than and intersecting said'bore, anelectrode secured to said tube and having a ring thereon normallyfitting said recess and cutting ofl communication between the bore andthe recess, and a single member operative to turn said tube and to raiseand lower the tube to move the ring into and out of fitting engagementwith said recessed part of the body portion to permit ,the bore to bebrought into open communication with the recess, substantially asdescribed.

2. The combination in a spark plug, of a body portion having a boreextending therethrough, a tube extending into and having a diametersmaller than the bore thus providing an annular passage around said tubeand extending to the outer surface of the body portion, said bodyportion having a recess at its innermost end, said recess being oflarger diameter than, and intersecting said bore, an electrode securedto said tube and having a ring thereon normally fitting said recess andcutting ofi communication between the bore and the recess, and a memberpivotally supported on said tube and having a cam designed to engage thebody portion and thereby move said tube longitudinally to open and closesaid bore with respect to the recess", substantially as described.

3. The combination in a spark plug, of a body portion having a boreextending therethrough, a tube extending into and having a diametersmaller than the bore thus providing an annular passage around said tubeand extending to the outer surface of the body portion, said bodyportion .having a recess at its innermost end, said recess being oflarger diameter than and intersecting said bore, an electrode secured tosaid tube 1 and having a ring thereon normally fitting saidrecess andcutting off communication between the bore and the recess, said tubebeing screw-threaded at its outer end, a nut 'a body having alongitudinal bore, and a recess in one end larger than the bore, and abeveled seat connecting the recess and bore, of a tube located in thebore ,3t ring'locatcd in the recess and adapted to engage the seat, amovable electrode projecting through the tube and the ring, a stationaryelectrode on the body, electrode relatively 'to the stationary elec-'trode,

said means also adapted to move the means for turning the movablemovable electrode longitudinally to move the ring away from its seat-andpermit priming liquid to' be poured through the bore of the body,substantially as described.

5. In a spark plug, the combination with .a body having a longitudinalbore, and a recess in one endlarger than the bore, and a beveled seatconnecting the recess and bore, of a tube located in the bore, a ringlocated in the recess and adapted to engage the seat, a'q'movableelectrode projecting through the tube and the ring, a stationaryelectrode on the body, a lever supported byv the tube and having a camportion for engagement with the body, said lever being adapted to movethe tube longitudinally and also adapted to turn the tube, substantiallyas described.

6. The combination in a spark plug, of a body portion having a boreextending therethrough, a tube extending into and having -a diametersmaller than the bore thus providing an annular passage around said tubeand extending to the outer surface of the body portion, said bodyportion having a recess at its innermost end, said recess being oflarger diameter than and intersecting said bore',-an electrode securedto said tube and having a ring thereon normally fitting said recess andcutting oif communication between the bore and the recess, said tube be?ing screw-threaded at its outer end, a nut fitting said screw-threadedportion, a lever pivoted on said nut and having a cam operative to movethe tube longitudinally when the lever is moved on'its pivot, a-secondnut on said screw-threaded end of the tube for engagement with the firstnut to lock the latter to the tube, said lever when the first nut islocked being operative'to turn the tube, substantially as described.

7 The combination in a spark plug, "of a body portion having a'boreextending therethrough, a tube extending into and having a diametersmaller than the bore thus providing an annular passage around said tubeand extending to the outer surface of the body portion, said bodyportion having a recess-at its innermost end, said recess being oflarger diameter than and intersecting said vbore,-an electrode securedto said tube and having a ring thereon normally fitting said recess andcutting off communication between the bore and the recess, the surfacesforming the side wall of the recess and the periphery of said ring beingshapedto provide a tapered annular recess between the ring and said bodyportion, substantially as described.

8. The combination in a spark plug, of a body portion having a boreextending therethrough, a tube extending into and having a diametersmaller than the bore thus provlding an annular passage around saidtubebody portion having a stationary electrode,

a member rotatable within said body portion and having a movableelectrode thereon, a collar carried by said member, a pointer on ;thecollar, means for'actuatmg said member to move the movable electrodetoward and from the stationary electrode, said body per tion having itsouter surface marked and in close proximity to the pointer whereby thelatter when the member is moved, will indicate the exact distancebetween the electrodes, substantially as described.

10. The combination in a spark plug, of a body portion having a boreextending there-- through, a tube extending into and having a diametersmaller than the bore thus providing an annular passage around sai'dtube and extending to the outer surface of the body portion, said bodyportion having a recess at its innermost end, said recess being oflarger diameter than and intersecting said bore, an electrode secured tosaidtube and having a ring thereon normally fitting said recess andcutting oft communication between the bore and the recess a singlemember operative to turn said tube and to raise and lower the tube tomove the ring into and out of fitting engagement with said recessed partof thecbody portion to permit the bore to be brought into opencommunication with the 'recess, and a, plurality of perforated layers ofmica interposed between the inner end of said tube and said ring,substantially as described;

, WILLIAM s. THOMAS. Attest:

EDNA E. Huoms,

